Machines for stripping unwanted material from cut blanks of cardboard and like material



May 10, 1960 KER 2,935,916

W. E. WAL MACHINES FOR STRIPPING UNWANTED MATERIAL FROM CUT BLANKS OF CARDBOARD AND LIKE MATERIAL Filed July 12, 1957 3 Sheets-Sheet 1 Imam-ova BY 1 ("AM MM ATTORNEYS May 10, 1960 w. E. WALKER 2,935,916 MACHINES FOR STRIPPING UNWANTED MATERIAL FROM cu'r BLANKS 0F CARDBOARD AND LIKE MATERIAL 3 Sheets-Sheet 2 Filed July 12, 1957 IW I I I IHI HHHI HHHHHHHI I 0|1| IH I II I I I I l lmlll ll... #3? m :1- Q

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MACHINES FOR STRIPPING UNWANTED MATERIAL FROM CUT BLANKS OF CARDBOARD AND LIKE. MATERIAL Filed July 12, 1957 3 Sheets-Sheet 3 ATT RNEYs ingthe unwanted material from the pins.

United States Patent William Edward Walker, Enfield, England Application July 12, 1957, Serial No. 671,500

Claims priority, application Great Britain July 20, 1956 6 Claims. (Cl. 93--36) This invention relates to machines for stripping unwanted material from out blanks of cardboard and like material either in separate sheets or a continuous web. In specification No. 2,778,286 I'have described a. machine for this purpose comprising two rollers between which the material .to be stripped is fed. One roller 20 carries pins so located that they pierce the unwanted material while the other roller has a surface adapted to receive the pins irrespective of the position of the pins. In order to remove subsequently the unwanted material from the pins, a comb was provided adjacent the first roller, the teeth of which engaged under the unwanted material and removed it from the pins. The pins them,- selves passed between the teeth of the comb.

Because of the necessity of passing between the teeth of the comb, theposition in which the pins can be placed on the first or stripping roller are to some extent limited. This reduces the flexibility of the machine in stripping blanks of any pattern and occasionally results in imperfect stripping because the pins cannot be located at the places suitable to pierce unwanted material properly.

An object of this invention is to provide improved means for removing unwanted material from the pins.-

According to the invention, a stripping machine forthe purpose described comprises a pair of rollers between which the blanks are fed, the first roller being adapted to have outwardly directed pins secured thereon at locations such that the pins pierce unwanted material of the blanks and the second roller having a surface adapted to receive the pins, and means for supporting and driving a; belt for removing unwanted material from the pins over a closed path which includes a part only of the periphery of the first roller including the bite of the rollers, at a peripheral speed substantially equal to the peripheral speed of the first roller.

The belt passes over the part of the first roller where it engages first with the blanks to be stripped and is pierced by the pins; the pierced unwanted material is thus held on the exterior of belt and when the belt subsequently leaves the surface of the first roller, -the belt .is withdrawn from the pins 'th'ereby 'automatically'rer'nov- The invention will be more readily understood by way of example from the following description of one form of stripping machine in accordance therewith, reference being made to the accompanying drawings, in which:

Figure 1 is a perspective view of the essential parts of the machine,

Figure 2 is a front view,

Figure 3 is a section on the line III-III of Figure 2, and

Figure 4 is an enlarged sectional view of part of the stripping roll.

Referring to the drawings, the machine comprises two co-operating rolls 12, 13 between which the material to be stripped is fed. The stripping roll 12 is a hollow steel cylinder 14 (Figure 4) having a rubber covering 15 and containing a gap 16 extending the full length across the the same pattern of pins.

cylinder. The ends of the cylinder are closed and the cylinder is driven through the shaft 17 carried in the frame 18. y

The second roll 13 is similar to the roll 13 of the above mentioned specification and has a covering of wire brush 13'. It is driven through the gearing 19 from roll 12. 1

Round the rubber covered surface of roll 12 is secured a tympan or pattern sheet 20 which is strong but is capable of being perforated at any point by pins 21. It is preferred to use strong paper for sheet 20 but sheet plastic, rubber cloth or wire mesh may alternatively be 7 used. Pins 21 are headed and are located on the sheet 20 in such positions that, when the sheet 20 is mounted on the roll 12 with the pin heads between it and the roller, each unwanted piece of material 22 is pierced by one or more pins as the material to be stripped comes within the nip of the rollers 12, 13. The number of pins employed for each piece of unwanted material is dependent on the size of the piece.

The pins 21 are received in the wire brush covering 13' of the roll 13 as described in the above mentioned specification.

As the roll 12 rotates the pierced unwanted pieces are carried away from the wanted material by the pins 21. Subsequently the unwanted material must be removed from the pins and this is effected by a belt 23. This belt 23 is made of strong paper or other strong flexible material that can be penetrated by the pins 21, such as plastic, rubber, cloth or Wire mesh, and extends over the width of the roll 12. Belt 23 is secured at its ends to two bars 24 carried between a pair of roller chains 25 passing over gear wheels 26 at the ends of roller 12 and an auxiliaryroll 27. Roll 27 is also journalled in the frame 18 and has a slot 28 which, like slot 16 of roll 12, receives the bars 24 as the belt 23 passes round the rolls 12, 27;

The machine illustrated intended to be fed with a cut blank on every second revolution of roller 12 and for this reason the belt 23 is shown as extending over only half the length of the chains 25, the arrangement being such that the belt passes over the roller 12 as shown during a stripping revolution. The chains have a length equal to twice the circumference of the roll 12, and the rolls 12, 27 have the same or different diameters, the gear wheels 26 having the same pitch diameters as the rolls on which they are mounted.

In operation, the belt 23 passes over the pattern sheet 20 on roll 12 and reaches the nip of the rolls 12, 13 slightly in advance of the leading edge of the blank to be stripped. It is therefore pierced by the pins 21and lies beneath the blank and, in particular, the pierced pieces of unwanted material. When the belt leaves tangentially the sheet 20 at the point 30 it is removed from the pins 21 and as it lies between the pins and the unwanted material it automatically frees that unwanted material from the pins.

By virtue of the ratio of the length of the chains 25 to the circumference of the roller 12, the belt 23 is always penetrated by the pins 21 at the same point for It is therefore capable of standing up to use for a long period of time and can be cheaply replaced when at last it becomes worn.

By providing belt 23 and by employing a pattern sheet 20 which is penetratable over its entire surface, there is no restriction on the positions on the pattern sheet at which the pins are inserted. It can therefore be ensured that, irrespective of the nature of the blank, a pattern sheet can be provided which will strip that blank with certainty. Furthermore, the removal of mi wanted material from the pins is, unlike previous methods, guaranteed by the operation of the belt.

When the stripping machine strips a blank on every revolution of the roller 12 the belt 23 extends continuously round the entire length of the chains 25, alternative halves of the belt being used on successive revolutions of roller 12.

In order that the wanted parts of the blank are prevented from following the surface of the roll 12 and therefore avoid the delivery means (not shown) located at the delivery side of the nip of rolls 12, 13, fingers 31 are carried at interevals on a shaft 32 within roller 12 and are adjustable along the shaft. The fingers 31 are L-shaped and the ends are secured to a second shaft 33 projecting through the end of the roller 12 and carrying a roller 34 travelling in a cam track 35 attached to the frame 18. This cam track is so arranged that as the leading edges of the wanted material leaves the nip of the rolls 12, 13, the fingers are pivoted on shaft 32 with the result that they project through apertures in the roll 12 and holes 36 formed in the pattern sheet 20 and belt 23 and force the wanted material away from the roller 12.

When a run ona particular type of blank is concluded, the pattern sheet 20 with the pins 21 held therein is removed from the roller 12 and stored for subsequent use. It is then replaced by another pattern sheet having pins 21 already located to suit the next blank to be stripped. At the same time it is preferable to place a new belt 23 in position.

I claim:

1. A stripping machine for stripping blanks comprising 'a first roller, outwardly directed pins detachably secured on the surface of said first roller in an irregular pattern selected to cause penetration of unwanted material in said blanks by said pins, a second roller co-oper'ating with said first roller and having a surface in which 'said pins' are receivable, a flexible sheet penetratable by said pins, and means detachably supporting and driving said sheet over a closed path which includes a part only of the circumference of said first roller including the nip of the co-operating rollers, at a peripheral speed substantially equal to the peripheral speed of said first roller, the length of said sheet being at least equal to that circumferential length of said first roller which carries said pins and the peripheral length of said closed path being exactly divisible by the distance travelled by one of said pins during a revolution of said first roller, whereby said sheet is penetrated by said pins at the same points in each revolution of said sheet over said closed path, unwanted material being removed from said blanks by the irregular pattern of pins, and the said sheet removing unwanted material pierced by the pins from said pins.

2. A stripping machine for stripping blanks according to claim 1 in which said sheet is made of strong paper penetratable at any point by the said pins.

3. A stripping machine according to claim 1 in which 'said second roller has a wire brush surface in which said pins are receivable.

4. A stripping machine according to claim 1 comprising also fingers mounted within said first roller and means for causing said fingers to project through slots in the surface of said first roller at a predetermined point in each revolution of said first roller to urge said stripped blanks away from the surface of said first roller.

5. A stripping machine for stripping blanks comprising a first roller, outwardly directed pins detachably secured on the surface of said first roller in an irregular pattern selected to cause penetration of unwanted material in said blanks by said pins, a second roller co-operating with said first roller and having a wire brush surface in which said pins are receivable, a flexible, initially imperforate disposable sheet penetratable by said pins and endless bands, upon which said sheet is detachably mounted, supporting and driving said sheet over a closed path which includes a part only of the circumference of said first roller including the nip of the co-operating rollers, at a peripheral speed substantially equal to the circumferential speed of said first roller, the length of said sheet being at least equal to the circumferential length of that part of said first roller which carries said pins, and the peripheral length of said closed path being exactly divisible by the distance travelled by one of said pins during a revolution of said first roller, whereby said sheet is penetrated by said pins at the same points in each revolution of said sheet over said closed path, unwanted material being removed from said blanks by the irregular pattern of pins, and the said sheet removing unwanted material pierced by the said pins from said pins.

6. A stripping machine for stripping blanks comprising a first roller, outwardly directed pins detachably secured on the surface of said first roller in an irregular pattern selected to cause penetration of unwanted material in said blanks by said pins, a second roller co-operating with said first roller and having a surface in which said pins are receivable, a flexible sheet penetratable by said pins, and means detachably supporting and driving said sheet over a closed path which includes only a part of the circumference of said first roller including the nip of the co-operating rollers, at a peripheral speed substantially equal to the circumferential speed of said first roller, and the peripheral length of said closed path being twice the distance travelled by one of the said pins during a revolution of said first roller, whilst the length 'ofsaid she'e'tis substantially equal to the distance travelled by one of the said pins during a revolution of said first r'oller, whereby said sheet is penetrated by said pins at the same points in each revolution of said sheet over said closed path, unwanted material being removed from said blanks by the irregular pattern of pins, and said sheet removing unwanted material pierced by said pins from said pins.

References Cited in the file of this patent UNITED STATES PATENTS 475,246 Morton May 17, 1892 1,402,251 Raymond Jan. 3, 1922 2,711,676 Richardson et al. June 28, 1955 2,778,286 Walker Jan. 22, 1957 

